Synergistic insecticidal compositions



United States Patent- 2,946,719 SYNERGISTIC INSECTICIDAL COMPOSITIONS Howard A. Jones and John A. Garman, Baltimore, Md., and Berton C. Dickinson, Lyndonville, N.Y., assignors to Food Machinery and Chemical Corporation, New York, N.Y., a corporation of Delaware No Drawing. Original application Mar. 24, 1955, Ser. No. 496,596. Divided and this application Oct. 23, 1958, Ser. No. 769,070

6 Claims. (Cl. 167-22) It is, in fact, quite probable that 'it"diflers"vvithdiliereiit synergistic combinations. The term synergism can be defined, however, as a cooperative action which is encountered in combinations of two or more biologically active components in which the combined activity of the two components exceeds the sum of the activities of the components when used alone. The insecticidal activity of the mixed components cannot be predicted from known values of the individual components, but is unpredictable and depends on the individual activity of neither.

It is an object of this invention to provide insecticidal compositions of enhanced killing power. Another object of this invention is to produce novel compositions contain ing compounds capable of synergizing the knockdown and killing properties of individual toxioa-nts. .A further object of this invention is to provide compositions including a relatively toxic phosphorus containing insecticide in which superior insecticidal activity is obtained because of the synergistic effects, but in which the ultimate toxicity to warm-blooded animals is greatly reduced because of the lower concentrations of the phosphorous compounds required when used in combination with the relatively less toxic carbamates. Other objects and advantages of the invention will become apparent from the description of the invention set forth below. 0

According to this invention, there are provided synergistic insecticidal compositions comprising 0,0-dimethyl S-(1,2-dicarbethoxyethyl) dithiophosphate and an organic carbamate ester having the following general formula NCOOR" wherein R is ethyl and R is selected from the group consisting of 2-naphthyl, furfuryl, l-naphthyl and Z-ethylhexyl radicals. These carbamates may be prepared as ice described in copending application Serial No. 812,113, filed May-11, 1959.

The synergistic insecticidal compositions of this invention may be used on a wide variety of insect and mite species, but are particularly effective against two spotted spider mites and the Mexican bean beetle. The combinations are highly effective and economical to use for such large-scale insecticidal requirements as the control of truck crop, forage crop and orchard insects.

The synergistic compositions of this invention can be formulated as aqueous emulsions, as dry or wettable powders, as solutions or in any other suitable vehicle. The insecticidal compositions can be utilized as sprays, as dusts, as Aerosol mixtures, insecticidal coating compositions, and as residues. In general, they can be applied by methods commonly used for control or eradication of insects, mites and the like. Thus these insecticidal compositions can be formulated with solvents, diluents and carrier media, adhesives, spreading, wetting and emulsifying agents and other ingredients. 3 I

The relative proportions of the active ingredients as well as inert carriers, solvents, dispersants and the like mayjvary within wide limits.

Thus the relative proportion (ratio) of the malathion tothecarbamate can range from 20 parts of the former per 1 part of the latter to 1 part of the former per parts of the latter and preferably about 1 part of the former to about 2 parts ofthelatter. .The quantities of the component toxicants'in the final insecticidal compositions can range from 0.01% to 25.00% for the malathion and from 0.05% to 50.00% for the carbamate, and preferably from 0.10% to 10.00% for the malathion and from 0.10% to 25.00% for the carbamate.

The procedures of the testing method are described below. The details of the test experiments including 7 the type of-formulation and mode of application or dosing,

and the species of insects which served astest subjects are given in theexamples.

The test method use is described as follows:

DUST TOWER METHOD This general method is described in the following ref erence, Moore, J. Econ. Ent. 43, No. 2, 188-190 (1950).

The dusting apparatus consists of a vertical glass cylinder, 34 inches high and 8.5 inches in diameter, into which hole in the center of the cover, by meansof a small I the appropriate dust sample is discharged through a small laboratory duster operating at an air pressure of 40 p.s'.i.g.

The duster assembly comprises a 10 ml. beaker, into which the weighed sample is placed, and fitted with a rubber stopper through which pass the air inlet and dust outlet tubes, both of which are made of inch diameter, copper tubing. At the outer end of the air inlet tube is a trigger valve that serves as a control for dispensing the dust. The inner end of this tube reaches nearly to the bottom of the beaker. The end of it is sealed but, along the sides, seven 0.032 inch holes are drilled at irregular intervals which serve as air inlets. Such an arrangement causes pronounced turbulence of the dust and thus insures exhausting the complete sample from the beaker. The dust outlet tube forms an arch from the top of the beaker to the top of the glass dusting tower.

After discharge of the sample into the tower, there is allowed a 2-minute settling time before removal of foliage or insects being treated. A weighed metal plate is placed in the tower each time a test is made, and by weighing the amount of dust deposited on it, it is then possible to calculate the amount applied per acre.

Because of day-to-day variations in the results obtained by this test method, comparisons among the individual components and their combinations were made simultaneously in order to minimize this source of variation.

Slight modifications in this test employed for specific insect species are as noted below.

Twp-spotted spider mite.-1n rests nu two-spotted :m'rtes, the mites were confined to the upper surfaces of potted bean plants by a Tanglefoot :ring. The bean plants were placed in the glass tower and the mites :direcbdnsted. Mortality readings were taken in 24 Only adult mites were used in determining mortality counts.

Mexican bean -beetle.--In tests using :this insect, bean foliage was dusted then infested with fourth instar Mexican bean beetle larvae. These were allowed to dead for 24 hours, then treated foliage was replaced with untreated. Mortality records were madeat-48 hours.

Squash b.ug.For this test squash leaves were collected in the field and the cut ends of the stern were wrapped in .moist cotton. Individual leaves were then placed in 3.5 inch Petri dishes and dusted as .descuibedzabove. Each treated leaf was then infested with '10 last instart squash bug nymphs and the covers of the Petri dishes were replaced. At the end of 24 hours the treated leaves were removed and fresh untreated leaves were introduced .into the dishes. Mortality counts were taken :after the bugs had been on the untreated leaves .for .2-4 hours.

4 an organic carbamate ester having the following general formula wherein R is ethyl and R is selected from the group consisting of 2-naphthy1, furfuryl, l-naphthyl and Z-ethylhexyl radicals, wherein said components are present in the.

ratio of about 2 parts of said carbamate per part of said dithiophosphate.

2. The method of killing insects which comprises applying to the insects and their habitat a synergistic insecticidal composition comprising 0,0-dimethyl S-(1,2-dicarbethoxyethyl) -dithiop'hosphate and an organic 'carbamate esterhav'iug the following general formula \NC 0.0116 f 33 wherein R is ethyl and R is selected from the group consisting of 2-naphthyll, t-rn'fury'l, l-nap'hthyl and Z-ethylhexyl radicals, wherein said components are present in the ratio of about 2 par-ts of said carba-mate per part of said difhiophosphate.

3.. Synergistic insecticidal compositions comprisingtlO- dimethyl S-(LZ-dicarbethoxyethyl) dithiophosphate and l-naphthyl N-ethyl carbamate, said components being present in the ratio .of about 2 parts of said carhamate ester to about 1 part of said dithiophosphate.

Table 1 /.1\l.('3-00.'l H

Oarbamate Phosphate "Rate Mortallt Dust Dust .(LbSJ Test Method Test Subject (Percent 114 R Cuuc. v Name Cone. As)

(Per- '(Percent) cant) EthyL 2-Naphthyl.. 1 22.2 Dust Tower-.- Mexican Bean Beetle 0 Malathiom. 0. 5 19. 8 Do 2-NaphthyL -1 d0 0.5 19.0 1110 PhenyL-" Benzyl--- 1 32.7 0 Malathiom- 0.5 '25.9 30 'Do Benzyl. 1 du-..- 0.5 28.3 90 Ethy Furfuryl.- 1 j24.7 0 lvlalathion. 0.5 1 9.8 0. Do. Furiuryl 1 -.d0 0.5 "20.7 -.d0.. 98 D do 1 6,9 Two-spot SpiderMite..- 4 Mulathionu 0.5 0.4, '28 Do.. Furfuryl-" 1 d0 0.5 5.3 51 Phsnyl TrichloroethyL- 1 9.3 Q Malathlon as .ao 130--.. TriehloroethyL. 1 'd0 10.5 8.3 97 Ethyl 1-Naphthyl- 0. 5 27.0 0 Malathion 0-25 27.3 0 130---. 1-Naphthyl 0.5 do 0.25 27.0 90 .DD- J 0.5 59.1 n- Malathlon 0.25 13.7 34 Do 1-Naphthyl. 0.5 do 0.25 10.5 100 Do- '2-Naphthyl.. 1.0 51.41 Malathiom- 0.25. 46.2' 0 130---. 2-Naphthyl 0.5.- 1o 0.25 45.6 90 130--.. .2-Ethylhexyl.- 1.0 25:9 -w Malathiom- 0.25 46.5 0 130.-.- 2-Ethylhexyl. 1.0 do 0.5 27.5

This table illustrates the unexpected effectiveness of in secticidal compositions of this invention against such insects as the Two-spotted spider mite and the Mexican beaubeetle.

This application is a division of copending application Serial No. 496,596 filed March 24, I955, now abandoned, which is a continuation-in-part of Serial No. 427,374, filed May '3, 1954, now abandoned.

We claim:

1. Synergistic insecticidal compositions comprising 0,0- dimethyl S-(l,2-dicarbethoxy'ethyl)dithiophosphate and 4. Synergistic insecticidal compositions comprising 0,0- dimethyl S-( Lidicarbethoxyethyl) dithiophosphate and Z-naphthyl N-ethyl carbamate, said components being present in the ratio of about 2 parts of said carbamate ester per part of dithiophosphate.

5. Synergistic insecticidal compositions comprising 0,0- dimethyl S-(1,2-dicarbethoxyethyl) dithiophosphate and furfuryl N-ethyl carbamate, said components being present in the ratio of about 2 parts of said carbamate ester per part of said dithiophosphate.

6. Synergistic insecticidal compositions comprising 0,0-

6 dimethyl S-(1,2-dicarbeth0xyethy1) dithiophosphate and OTHER REFERENCES 2-ethylhexyl N-ethyl carbamate, said components being present in the ratio of about 2 parts of said carbamate ester Chemlcal 1631 1950 per part of said dithiophosphate. Sharp: Agr. News Letter, January-February 1952, pp.

5 13. References Cted the file ffl11s Pamnt Roark: U.S. Dept. Agr. Bull. E-344, May 1935, pp.

UNITED STATES PATENTS 2-6. 7 2,503,390 Jelinek Apr. 11, 1950 Frear: Chem. of the Pesticides, 3rd ed., January 1955,

2,679,508 Gysin May 25, 1954 pp. 73-91. 

1. SYNERGISTIC INSECTICIDAL COMPOSITIONS COMPRISING O,ODIMETHYL S-(1,2-DICARBETHOXYETHYL) DITHIOPHOSPHATE AND AN ORGANIC CARBAMATE ESTER HAVING THE FOLLOWING GENERAL FORMULA 